jQuery can be used in many types of applications, as it helps to write the things you do a lot as a web developer much quicker.

Another is single page applications, where the actual page content is requested using ajax and the page never loads the entire page again, instead just replacing the content that needs to change.

Ajax (Asynchronous JavaScript And XML) is not a programming language – it is a technique for accessing web servers from a web page. With Ajax, you can update a web page, request data from a server, receive data from a server, and more – all without reloading the page.

JQuery is a JavaScript framework, you can use Ajax calls with Jquery like so: $( "#contents" ).load( 'page.html #about' ); which will asynchronously load html from “page.html” from a div/section with id of ‘about’ into the current page.